1. Field of the Invention
The present invention relates to cap dispensing closures for a container, more particularly to closures having a chamber in the cap that can selectively store and dispense the contents there-of into the container.
2. Prior Art
The broad concept of a container closure including a compartment for storing material separate from the container for selectively mixing with the container is very old and well known.
U.S. Pat. No. 3,521,745 discloses a container with two compartments and a piercing member used to rupture the wall between the compartments to allow the material stored in one compartment to mix with the material in the other.
U.S. Pat. No. 3,603,469 discloses a container closure having a cap that forms an interior chamber or reservoir for storing a substance. A reciprocating piercing member is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 3,715,189 discloses a container with a completely open top (i.e. no neck finish) with a top cover that includes an interior chamber or reservoir for storing a substance. A plunger is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 3,968,872 discloses a container closure having a cap that forms an interior chamber or reservoir for storing a substance. A piercing member is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 4,195,731 discloses a container closure having a cap that forms an interior chamber or reservoir for storing a substance. A piercing piston is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 4,221,291 discloses a container closure having a cap that forms an interior chamber or reservoir for storing a substance. A plunger or rod is connected to the bottom wall of the reservoir and is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 4,615,437 discloses a threaded container closure or cap that forms an interior chamber or reservoir for storing a substance. A bottom wall of the reservoir is held in position by the bottle neck finish and further threading of the upper portion of the cap onto the bottle is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 4,858,760 discloses a container closure having a cap that forms an interior chamber or reservoir for storing a substance. A bottom wall of the reservoir is ruptured by a piecing plunger to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 4,903,865 discloses a threaded container closure or cap that forms an interior chamber or reservoir for storing a substance. A bottom wall of the reservoir is held in position by the bottle neck finish and movement of a reciprocating plunger on the cap into the bottle is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 5,029,718 discloses a container closure or cap that forms an interior chamber or reservoir for storing a substance. A bottom wall of the reservoir is held in position by the bottle neck finish and movement of a reciprocating plunger on the cap into the bottle is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 5,038,951 discloses a container closure or cap that forms an interior chamber or reservoir for storing a substance. A bottom wall of the reservoir is held in position by the bottle neck finish and movement of a reciprocating plunger on the cap into the bottle is used to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 5,772,017 discloses a threaded container closure or cap that forms an interior chamber or reservoir for storing a substance. A bottom wall of the reservoir is ruptured through movement of a threaded reciprocating piecing member on the cap to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 5,950,819 discloses a threaded container closure or cap that forms an interior chamber or reservoir for storing a substance. The reservoir is held in position by the bottle neck finish and movement of a top of the cap into the bottle is used to rupture the side walls of the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 6,165,523 discloses a threaded container closure or cap that forms an interior chamber or reservoir for storing a substance. The reservoir is collapsible and has a piecing member for piercing the bottom wall thereof during compression to rupture the reservoir to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 6,224,922 discloses a container closure or cap that forms multiple colorants reservoirs for selectively dispensing into the container to selectively color the beverage in the container.
U.S. Pat. No. 6,305,576 discloses a threaded container closure or cap that forms an “aseptic” interior chamber or reservoir for storing a substance. A bottom wall of the reservoir is pieced by a movement of a reciprocating piercing member to allow the material stored in the reservoir to mix with the material in the container.
U.S. Pat. No. 6,372,270 discloses a container closure or cap that forms an interior chamber or reservoir for storing a substance. A bottom wall of the reservoir is ruptured by movement of a reciprocating plunger on the cap into the bottle to allow the material stored in the reservoir to mix with the material in the container.
As noted above wide variety of cap dispensing, or cap ejecting, closures are known in the art. The prior art devices have certain drawbacks. Many of these earlier designs do not allow for the formation of the cap chamber out of a high moisture/oxygen barrier material. Materials that form a high moisture/oxygen barrier are generally too rigid to form undercuts that can be jumped out of a mold. Materials that can economically form the components do not yield the high moisture/oxygen barrier and limits the applicability of the closure (e.g. certain material in the chamber would have a low shelf life due to the material selection for the cap). Further, many of these prior art designs are impractical from a standpoint of filling the chamber or reservoir in the closure.
It is an object of the present invention to overcome the drawbacks of the prior art and provide an economical unit dosage dispensing closure with high moisture/oxygen barrier characteristics for the chamber and which is easily filled having a long shelf life.